The phrase "casting aspersions on" typically means to attack or criticize someone's reputation or character. The antonyms for this phrase would include words or phrases like praise, compliment, commend, laud or applaud. These words indicate positive recognition or respect for a person or their actions, rather than criticism or blame. Instead of casting aspersions, one can offer sincere appreciation and recognition of someone's positive qualities, achievements, and contributions. Using antonyms can help us avoid negative language and promote a culture of positivity and support in our interactions with others.